The present invention relates generally to spinal fixation systems, such as systems for use in the fixation of the spine for the treatment of various spinal deformities. Specifically, the present invention contemplates a lateral connector assembly for interconnecting an elongated member, such as a rod or tether, with a bone engaging fastener such as a hook, screw or bolt.
The treatment of spinal deformities and injuries has evolved significantly over the last 30 years. Spinal deformities, such as scoliosis and kyphosis, as well as fractures, spondylolisthesis, and other medical indications have been treated using a system of relatively rigid elongated members spanning the vertebral column. In one type of system, the elongated members constitute a plate that has a number of openings or slots through which bone bolts or bone screws extend. The bone engaging fasteners are threaded into different aspects of the vertebra and fixed to the plate to achieve fixation of the elongated plate. In other procedures, elongated rigid rods are joined to screws or hooks embedded in the spine to fix the relative position of each vertebra. In yet further procedures for dynamic stabilization, an at least partially flexible elongate member is joined to bone engaging fasteners embedded in the spine.
In the implantation of any spinal instrumentation, one goal of the surgeon is to minimize the intrusion into the patient, whether by the amount of implants that must be used, the size of the surgical access opening or by the length of time required to fix the implants within the patient. Further, the system must be easy to use and provide the surgeon with confidence that it will provide the desired stabilization after implantation.
While connectors have been provided that offer various degrees of freedom of movement between the elongated member and the bone fastener, there remains a need for providing an improved connection between the bone fastener and the elongated member.